1. Field of the Invention
The present invention relates, in general, to lumbar supporting devices for vehicles and, more particularly, to a lumbar supporting device for a vehicle, which simultaneously pulls both the upper and lower ends of a lumbar plate towards a lumbar support part when a lumbar support is in operation to always keep the lumbar support part at a constant position without changing position, thus optimally maintaining a passenger's posture, reducing the number of parts, and simplifying the construction, therefore reducing manufacturing cost and increasing operating speed.
2. Description of Related Art
Generally, the seats of a vehicle are divided into front and rear seats.
The front seat is mounted to be pulled forwards or pushed backwards according to the driving habit and body condition of a seated driver and the body condition of a passenger who is sitting in the rear seat. Such a front seat is provided with a seat back to comfortably support the driver's back.
A seat back frame and a lumbar support are installed in the seat back. The lumbar support is mounted to the seat back frame to comfortably support a passenger's loins.
Generally, such a lumbar support is designed biomechanically to comfortably support the passenger's lumbar.
As shown in FIG. 1, a conventional lumbar supporting device for a vehicle includes a lumbar plate 1, a plate spring 3, and a wire 5.
When the wire 5 is pulled by external power, the plate spring 3 is bent, so that the lumbar plate 1 protrudes. A passenger's loins are supported by the protruding lumbar plate 1.
Generally, in the conventional lumbar supporting device for the vehicle, the lower end of the lumbar plate 1 is fixed. In this state, a side of the lumbar plate 1 is pulled by the wire 5.
Thus, the conventional lumbar supporting device is problematic in that the protruding part of the lumbar plate 1 for supporting the passenger's loins may fluctuate up or down.
If the protruding part of the lumbar plate 1 fluctuates, the passenger's loins cannot be supported at a correct position, thus inconveniencing the passenger, therefore deteriorating ride comfort.
Further, the conventional lumbar supporting device for the vehicle is problematic in that the number of parts is large and the construction is complicated, so that the conventional lumbar supporting device is applied to only medium and large vehicles.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.